The present invention relates to the field of construction, civil engineering and public works, more particularly the covering of large surfaces by means of strips of sealing, insulating and/or protective material, and has for its object a movable machine for laying a thermoweldable covering strip, preferably self-propelled.
1. Description of the Related Art
There are already known machines of the mentioned type in which the strips of thermoweldable covering are subjected to indirect heating means before their application to the support to be covered.
These machines, known particularly from FR-A-2 689 151 and FR-A-2 718 164, comprise more particularly a heating cylinder enclosing a bath of heated oil, the covering strip circulating over this cylinder with its thermoweldable surface in intimate contact with the surface of the latter immediately before its application to the support to be covered.
However, these machines have numerous drawbacks, among others of which could be cited, on the one hand, a leveling, a tearing off and/or a carbonization of the binder of the thermoweldable surface of the covering, on the other hand, a deposit of binder on the heating cylinder requiring repeated cleaning operations and, finally, a limited speed of laying, given the type of indirect heating, by contact, that is used.
Similar drawbacks have been encountered for machines of the mentioned type, in which the heating cylinder integrates an exposed flame heating means, which is, because of this fact, more delicate and risky in operation.
Moreover, the heated cylinder machines with an oil bath require circuits for circulation of fluid and for heating that are complex and bulky, which cannot be used to heat the support prior to its application and require providing a type of supplemental heating means to carry out, as the case may be, this preparation of the support.
However, such a preliminary operation of preparation of the support constitutes an element favoring the adhesion of the applied strip.
2. Summary of the Invention
The present invention has particularly for its object to overcome at least certain of the mentioned drawbacks.
To this end, the invention has for its object a machine for laying a thermoweldable strip covering, preferably self-propelled, comprising a movable support chassis provided with means for support, for unrolling and for application of at least one strip of rolled-up covering, characterized in that it comprises at least one unit for the production of hot air prolonged by an ejection nozzle provided with an outlet opening in the form of a transversely extending slot and of which the outlet flow is directed toward the thermoweldable undersurface of the strip covering immediately before its application to the support to be covered.